Morphometrical analysis on topographical difference in size distribution, number and volume of islets in the human pancreas.

Abstract

Seven pancreases from nondiabetic autopsy cases were submitted to morphometrical analysis of the islets of Langerhans as a preliminary investigation of the diabetic pancreas.The pancreatic islets were approximately simulated by spheres of different sizes randomly dispersed in the three-dimensional space; thereon the parameters of Weibull function assumed for the distribution of islet radii were estimated stereologically from chord length measurements on histologic sec tions taken from different portions of the pancreas.By means of the estimated parameters topographical comparison of the number, volume, mean radius and size distribution of islets in a unit volume was performed. The islet distribution appeared to change the pattern gradually according to the position from the pancreatic head to the tail: the head was characterized by abundance of small islets that corresponded to a slightly higher islet population thereat, whereas the tail by moderate increase of larger islets that caused a steep increase of islet volume here. To estimate parameters for the whole pancreas a histologic section from a range between the midposition of the pancreas and the one-fourth position from the splenic end was regarded to be a fairly good representative.-pancreatic islets; spherical bodies; size distribution function; parameters; topographical comparisonThe pancreatic islets are regarded as a group of spherical or ellipsoidal bodies of different sizes randomly dispersed in the three-dimensional space. In quantitation of the islets in the pancreas, as has been stressed by some authors (Lazarus and Volk 1962;Warren et al. 1966), it is impossible to make an adequate estimation immediately from observations of distribution of islet sections on a histologic slide.Using a large number of alternate serial sections from a monkey pancreas, Thompson (1932) and Thompson and Hussey (1932) made an attempt at analyz ing the density and frequency distribution of the volume of the three-dimensional structures for which they did not consider any appropriate geometrical model. For assessment of the population density they measured the diameter of randomly

Lack of compensatory increase in islet blood flow and islet mass in GK rats following 60% partial pancreatectomy

“…However, replication per se has not been evaluated in the present study. As expected (see Hellman 1959, Saito et al 1978, Hellerström et al 1988, islet cell mass was higher in the splenic portion of the pancreas in Wistar rats. This pattern of distribution was also present in hybrid and GK rats.…”

The size and number of Langerhans islets correlated with their endocrine function: A morphometry on immunostained serial sections of adult human pancreases.

“…The tissue slices were cut perpendicular to the long axis of the pancreas at the tail 5 cm from the splenic end, a place considered most representative of pancreatic tissue on account of the relatively constant density of islets (Saito et al 1978). After fixation in 10% formalin, the slices were embedded in paraffin and a total of 770 serial sections 2,um thick were prepared from Case 1, 440 from Case 2 and 808 from Case 3.…”

Current Status of Clinical Islet Transplantation

“…In a study involving seven pancreases, the total number of islets varied between 3.6 and 14.8 million (19), and the total islet volume was 0.5 to 1.3 cm 3 . In that study all islets were included, and a large number of small islets dominated the reported value.…”